The biggest lesson learned from spending time with the greatest traders of the past generation, including Jim Rogers, Marty Schwartz and Paul Tudor Jones, is not to be afraid to lose money, says Jack Schwager, author of "The Little Book of Market Wizards". Schwager says these market wizards embrace their mistakes, and profit from them in the future. They also pick trading styles that match their personalities. Finally, Schwager explains why the most successful investors play defense first.

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